Relief valve



Feb. 13, 1940. CRQWLEY 2,190,352

RELIEF VALVE Filed April 6, 1937 INVENT OR.

Jl Jl Patented Feb. 13, 1940" RELIEF VALVE John C. Crowley, signor to The Cleveland Heights, Ohio, as- Dll Manufacturing Company,

Cleveland, Ohio, a corporation of Ohio Application April 6, 1937, Serial No. 135,289

1 Claim.

This invention relates to apressure relief valve andf although a valve Iembodying the invention might advantageouslybe'used in various relations where it is desiredto automatically relieve pressure upon afpredetermined pressure being obtained, the vinvention will be described hereinr with` reference to a pressure `relief valve for a receptacle of the; type containingy uid under pressure, inasmuch as the pressure relief valve of the invention-has particular utility when thus employed.

y An object of the present invention is to provide" a pressure relief valve which is efficient and ac- Ycurate lin operation.

- valve, which' While being accurate and eicient in operation, can be made relatively small in size and will be economical to manufacture.

A still further object is tovprovide a pressure relief valve r that is sturdy in'vconstruction, can

be readily; adjusted for different predetermined pressures, andwhich will not get out of order or require servicingin use.

Further and additional objects and advantages not hereinbefore specified will become apparent hereinafter during the following detailed description of an embodiment of the invention` which is illustrated in the accompanying drawing, wherein Fig. 1 is anelevational View, on a greatly reduced-scale, of va receptaclegadapted -to contain yvalve mounted therein.

pressure fluid, certain portions of the receptacle being broken away to show the pressure relief Fig. 2 is a sectional view through the pressure :relief Valve embodying-,the invention and a portionof the receptacle,y closure ona greatlyrenlarged y scale.

Fig.A` 3 is a bottom yplan-view of the pressure reliefvalve shown in Fig. Zand Fig; fl'is a fragmentary sectional View similarv to Fig. 2 but showing the valve of the .pressure relief valve vin open position to relieve the pres-` sure, the vdistance to which the valve has moved to open position being greatly exaggerated.

Although va pressure. relief valve embodying the present invention, can, as has been .previously stated, be used advantageously in a wide Variety ed in a receptacle containing pressure fluid, With the understanding, however, that `this use is merely by way oi example and without any in-4 tention to limit the invention thereto.

The receptacle ID shown in Fig. 1 can be any Well known type of receptacle that contains pressure fluid, and may be closed at its upper end by a top closure member I I. In the illustration the pressure relief valve embodying the invention is shown as supported by the cover member II and extending into the receptacle, it being understood, however, that the pressure relief valve could be mounted in the receptacle in different locations and in different ways. n

The closure member II of the'receptacle is l provided with a counterbore threaded as indicated at i2 and communicating at its bottom with a centrally disposed reduced opening or bore extending through the closure member from the counterbore to the inner side of the member. A suitable sealing gasket I3 may be provided at 'the bottom of the counterbore for a purpose which will soon become apparent.

The pressure relief valve comprises a tubular member I4 having an enlargedthreaded upper end I5, and said tubular member extendsthrough the opening in the closure member and is secured in position by the enlarged threaded upper end i5 of the tubular member being screwed into the threaded counterbore I2 of the closure member.

When the tubular member is fully positioned in the receptacle the upper end of the enlarged portion I5 should lie flush with the outer side of the closure member II, while the sealing gasket I3 at the bottom of the counterbore will be compressed between the shoulder formed by the enlarged portionv I5 of the tubular member and the bottom ofthe counterbore. The upper end of the enlarged portion l5 of the tubular member may be'provided ywith longitudinally extending cut-outs or recesses I6 with whicha Wrench or other suitable tool can be engaged to facilitate the mounting of the tubular memberin the closure member. The tubular'member is provided with a bore Il extending from the lower endof the member andcommunicating at its upper end with'an enlarged counterbore I8 forming in the tubular member an interior annular shoulder I9. y

The upperend of the counterbore I8 is threaded, as indicated at 2d. p

A member, which will be termed herein a barrel since itis somewhat similar to the barrel of l the usualvalve insides or Valve core employed i UNITE; y STATES. eArENr voFFilC-Ef of relations, itfwillbe described'herein as mountl in a valve stem, is indicated at 2|, and said barrel is provided with a bore 22 extending therethrough from end to end. Adjacentvthe upper end of the barrel but inwardly thereof the barrel is provided with an integral annular flange 23 of a diameter such as to have a sliding fit in the counterbore i8 of the tubular member I4. The lower end of the barrel is in the form of a substantially conical enlargement 24 that terminates in a narrow edged valve seat 2da. A rubber sealing tube 25 has its upperend secured to the barrel preferably by vuloanization, intermediate the flange 23 and the enlarged conical portion 24. This tube 25 extends downwardly of the bore of the tubular member ylil and is provided at its lower end with an annular outwardly extending bead or rib 23 that projects into a complew mentary groove or recess formed in the tubular member i4. The barrel 2i will normally be in the position shown in Fig. 2, wherein the flange 23 will engage the shoulder i@ provided at the bottom of the counterbore i8v in the tubular member, which engagement positively limits the inward or downward movement of the barrel.

Under certain conditions which will later be referred to, the barrel 2i will be'moved upwardly or outwardly in the tubular member ifi, whereupon the ilange 23 will be out of engagement with the shoulder i9 at the bottom of the counterborev i8 in the tubular member and` will lie above the same, as indicated in Fig. 4.. f

Inasmuch as the sealing tube 25 is formed of rubber or other elastic material and'is connected to the barrel 2| and to the tubular member I il by the rib or bead 26, it will be seen that the upward movement of the barrel will act to stretch said tube, and when the barrel moves back from the position shown in Fig. 4 to the position shown in Fig. 2 the tube 25 will return to its normal condition. The tube 25 acts as a sealing means to prevent the escape of pressure fluid between the barrel 2| and the tubular member ifi, and hence any pressure fluid passing outwardly through the pressure relief valve must pass through the bore 22 in the barrel.

This bore 22 through the barrel 2l is normally sealed by a valve formed of a cup-shaped member 2l and carrying within the cup thereof a flexible gasket or packing 26 adapted to engage the valve seat 2da and seal the passage through the bore 22 of the barrel.

The valve'just referred to is fixed on a Valve -pin 29 which has a portion 29a extending above the valve and into the bore 22 of the barrel 2| andserving as a centering and guiding means for the valve and a portion 29h which extends below the valve and is provided at its lower end with a head 29o, this last named portion 29h passing through a tubular bushing 3d secured in the lower end of the bore l'l in the tubular member ifi and provided at its lower end with a narrow downwardly extending bridgeor abut--v ment strip 30a having a centrally disposed open` ing through which the portion 22h of the valve stem extends.

It will be seen that pressure iiuid can readily pass into the bushing Sil and into the tubular member i4 `around the bridgev or 'abutment strip 30a. A relatively weak coil spring 3l is mounted on the portion 29h of the valve stem between the lower side of the cup 2 of the valve and the inner or upper side of the bridge or abutment strip 30a, and said spring will act to urge the Valve upwardly into seating position and `until the head 29eA engages the bridge or abutment strip 30a,

as indicated in Fig. 4, at which time upward i' movement of the valve will bev positively halted;

The barrel 2| is normally held in the position shown in Fig. 2, that iswith the ilange 23. in

engagement with the shoulder I9 at the bottom of the counterbore I8 in the tubular member M,

by means of a relatively heavy -or strong coil" spring 32 arranged in the counterbore and abutting at one end the upper side ofthe ange 231, and at its opposite' side the undersideof .aj

threaded adjusting plug 33y having a central opening 30. and which can be screwed inwardly or outwardly of the counterbore I8 which `is provided with threads 20 adjacent its outer end' as has already been stated. The tension of the.

spring 32 is adjustedby means ofthe adjusting plug 33 to exert a predetermined pressure upon f sure at which the relief valve should open to relieve the `pressure of the pressure uid, as

' the barrel 2| and in accordance with the pre'swill later become more apparent I'I'he;spring.`

3| should be of a tension such thatthevalvewwill be held seated thereby under `normal pressures,`

when the barrel is in the position shown in Fig. 2. Assuming the pressure relief Valvetorbejmounted in position in a receptacle containing pressure."

fluid and the tension of the spring 32 to have" been set for the valve to function at apredetermined pressure, the operation'jof the .pressure relief Valve will now be explained.

, sol- When the pressure of the pressurefiluid vin I f the receptacle does not equal the predetermined.

pressure referred to above, the parts of the pressure relief valve will be in the rposition indicated inv Fig. 2 and the Valve will be seated in sealing engagement with the valve seat 24a on the lower end ofthe barrel 2|, the sealing tube 25 preventi ing the escape of pressure fluid outwardly of the tubular member vI4 between it and the barrel. At

this time the pressure fluid is acting, in'conjunce tion with the spring 3|, upon the surface of, the

cup-shaped member 2l of the valvefto `urgethe y valve upwardly or outwardlyinto seating posi-I.

tion. conically enlarged portion 24 of the barrel 2| and tending to move the barrel youtwardly but not eifecting lany. outward movement thereof,

since the spring 32 is maintaining the barrel in z position with the flange 23 in engagement withv the shoulder I9. However, should thel pressure of the 'pressure fluid in the receptacle increasel for any reason to a point where it equals or is" greater than said predetermined pressure lfor which the relief valve is set, the force exerted thereby o n the cup 2l of the valveand upon the enlarged conical portion 24 ofthe barrel 2i will.

The pressure iluid is also acting on the move the barreland valve upwardly against thev j action of the spring 32.y The upward movement oi"` the `valve `will cease las soon as the heady 29ek of the valve pin abuts the bridge or abutment Hence, rthe `con`` tinued upward movement of the barrelI 2| under strip 30a of the bushing 30.-

the action of the pressure `fluid will unseat `the valve with respectto the .seat 24aA at thelower end of the barrel, and the pressure fluid will Abe the position shown in Fig. 2 and-the valve will:

engage the valve seat 24a and thus seal the passage through the barrel and prevent thefurther 6.5 free to iiow around the valve and into and" through the bore 22 in the barrel .and through a central opening 34 in the plug 33- and thence,` in this instance, to atmosphere. As soon as the. i

reduction n pressure yof the vpressure uid in the receptacle.

It will be understood that during the move- I ment of the barrel 2| just referred to, the sealing ltube 25 will stretch and contract as the case may be. As already stated, Fig. 4 illustrates lthe parts in the position wherein thevalve isv disengaged from the valve seat 24a,.but it should be understood that the distance upwardly to which the barrel is shown as having moved is greatly exaggerated in this view for the purpose of clear illustration. In actual practice the barrel would only move a short distance upwardly and the separation of the valve seat 24a andthe gasket 28 of the valve would be very slight, infact would constitute a mere crack, but this would be sufcient to relieve the pressure of the pressure fluid duction in' pressure as ,soon as the .pressure of the pressure fluid reaches or rfalls below, as the case may be, the predetermined pressure for which the spring 32 has been adjusted. In addition, the pressure vrelief valve embodying the invention is relatively simple in construction and yis formed of parts which while sturdy can bet manufactured economically.

Although a preferred.

bodiment of the in-v vention has-beeny illustrated' and described herein, it should be understood that the invention tations within the scope of the appended claim. `Having thus described my invention I claim: A pressure relief valve comprising a tubular member adapted to have one of its ends in comis susceptible of various modifications and adapmunication with pressure fluid while its oppoingl a counterbore therein adjacent saidoutlet end and a bore extending therethrough from said counterbore to said inlet end, av barrel located in said member and having a valve seat at one end thereof and a bore therethrough, said barrel being f movable longitudinally of said member vand having adjacent its other end a ange slidably fitting said counterbore and engageable with site end constitutes an outlet, said member havthe. bottom thereof to limit movement of the barrel in one direction, an elastic tube interposed between said barrel and the wall of said bore in said member and having `one of its ends secured to saidl barrel intermediate ysaid valve seat and said flange and its opposite end secured to said member, a Valve movable longitudinally of said member, means tending to move said valve against said` valve seat on said barrel,

means tending to move said barrel in the opposite directionand toward said'valve with a predetermined pressure, and means limiting said movement vof said valve, said barrel being provided with a surface upon which pressure fluid can actvto move said barrel against the action I of said second named means and in a direction away from said valve. c

JOHN C. CROWLEY. 

